Continuing advances in system architecture, e.g., multi-core processing, and advances in application require corresponding advances in memory systems. High capacity memory is becoming increasingly important with increases in the number of cores in a processor system the number of applications, e.g., in-memory databases and virtualized servers, that require significantly higher memory capacity. The ability to scale existing memory systems (e.g., double data rate direct in-line memory modules (DDR DIMMs)) is limited due to several factors including cost, power consumption, density, and performance. A typical large memory platform may contain as many as 16 DIMMs or greater. This creates challenges in component placement, cooling, as well as routing of signals, all of which adds to the cost of these systems.
In addition to capacity, persistent memory is increasingly useful in certain applications. A typical example is an in-memory database where the time to build the memory image can be considerably large as the size of the database grows. The ability to maintain the memory contents across power cycling may reduce start-up time and remove the requirement for redundant active or stand-by servers.
Accordingly, hybrid memory devices may find utility.